Converging Lenses and Magnification

[mikezhou]

I'm in the middle of studying for the MCAT, and just want to get all the concepts instead of memorizing how to solve problems. I'm having a hard time understanding converging lenses.

From what I understand, converging lenses create real images that are inverted. This property of inversion means that the magnification should be negative, where m = - (i / o). Since the image (i) is a positive number (real) and the object is a negative number (other side of lens), how is it possible that m is negative? i.e. - (positive/negative) = positive

What am I missing here?

My appreciation in advance!

 

[Doc Al]

Since the image (i) is a positive number (real) and the object is a negative number (other side of lens), how is it possible that m is negative?

The usual sign convention (there are several) treats object distances as positive if the object is in front of the lens (as usual).